Final answer:
The gravitational force between objects is affected by their mass and distance apart, with greater mass increasing the force and greater distance decreasing it.
Step-by-step explanation:
The pair of factors that affects the force of gravity between objects is mass and distance. This is described by Newton's law of universal gravitation, which states that the gravitational force is directly proportional to the product of the masses of the two objects involved and inversely proportional to the square of the distance between their centers. Hence, as the mass of either object increases, the gravitational force increases, and as the distance between them increases, the gravitational force decreases.